Muscles that AID in mastication

Question 1

Temporalis

Answer 1

ORIGIN
Temporal fossa.

INSERTION
Coronoid process of the mandible.

ACTION
Elevates and retracts the mandible.

INNERVATION
Trigeminal nerve (CN V).

Question 2

Masseter

Answer 2

ORIGIN
Zygomatic arch.

INSERTION
Ramus of the mandible.

ACTION
Elevates mandible.

INNERVATION
Trigeminal nerve (CN V).

Question 3

Internal and external pterygoid

Answer 3

ORIGIN
Pterygoid plate of sphenoid bone.

INSERTION
Mandible.

ACTION
Elevates mandible (closes jaw), protrudes mandible (forward), moves mandible to one side.

INNERVATION
Trigeminal nerve (CN V).

Question 4

Buccinator

Answer 4

ORIGIN
Maxillary bone and mandible.

INSERTION
Blends with fibers of orbicularis oris.

ACTION
Assists in mastication by holding (compressing) cheeks close to teeth.

INNERVATION
Facial nerve (CN VII) .